bin: Improve the run-as-root confirmation prompt
bin: Improve the run-as-root confirmation prompt

  * Send the prompt to stderr
  * Print "> " without a newline so the user knows it is a prompt
  * Wrap long lines
  * Use a here-document

ether/etherpad-lite,storytouch/etherpad-lite,ether/etherpad-lite,storytouch/etherpad-lite,storytouch/etherpad-lite,ether/etherpad-lite